Expandable implement attachment

ABSTRACT

An expandable implement attachment selectively connectable to a vehicle and having a frame assembly, a first bucket member laterally fixed to the frame assembly and a second bucket member laterally moveable relative to the frame assembly to provide a bucket with an adjustable width.

RELATED APPLICATION

This application claims the benefit of Provisional Application Ser. No.60/607,563 filed Sep. 7, 2004.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to an expandable implementattachment and more particularly to a selectively expandable andretractable bucket/scraper designed for connection to a driven vehicleor implement such as a tractor, truck, skid steer vehicle or the like.

2. Description of the Prior Art

Implement attachments such as loading buckets, scrapers and the like areavailable for selective attachment to a wide variety of self-propelleddriven vehicles or implements such as tractors, trucks, bulldozers, skidsteer vehicles and the like. These implement attachments are selectivelyattached to and detached from such vehicles by quick attachmentmechanisms known in the art.

For the most part, such implement attachments have a fixed configurationand size which is designed for performing a particular task such aslift, carry and dump or pushing or scraping, etc. Thus, if differenttasks need to be performed, this normally involves changing implementattachments. Further, implement attachments such as buckets and scraperscome in a variety of sizes with different load capacities, differentwidths, etc. Thus, if a bucket with a different load capacity or abucket or scraper with a different width is needed or desired, severalimplement attachments must be maintained and periodically attached toand detached from the vehicle as particular needs change. This requiresthe maintenance of an inventory of several implement attachments such asloading buckets of different capacities and scrapers and buckets ofdifferent widths. Significant downtime is also required to change fromone implement attachment to another. Further, when the business of thedriven vehicle owner requires travel to a variety of work sites orlocations such as snow removal and the like, the transport of severalimplement attachments to those work sites is often required.

Accordingly, there is a need for a single implement attachment or alimited number of implement attachments which are capable of performinga variety of tasks such as lift, carry and dump as well as scraping andwhich are capable of being adjusted to provide different load capacitiesand different widths.

SUMMARY OF THE INVENTION

In contrast to the prior art, the present invention provides animplement attachment which is capable of performing a variety of tasksand is capable of adjustment to different load capacities and differentwidths. More specifically, the present invention is directed to aselectively expandable and retractable bucket/scraper attachment for adriven vehicle such as a truck, tractor, skid steer vehicle or the like.Although the preferred implement attachment of the present invention maybe attached to the front or rear of a driven vehicle, it has particularapplicability as a front end loader/scraper.

In a preferred embodiment, the implement attachment of the presentinvention includes a center bucket and a pair of selectively expandableside buckets or side bucket extensions which are controlled via thehydraulic system of the driven vehicle. The bucket extensions aremovable between a retracted position in which the implement attachmentfunctions as a loader and/or scraper with a first load capacity andwidth and an expanded position in which the implement attachmentfunctions as a loader and/or scraper with a second load capacity andwidth. For example, in the preferred embodiment, a six foot wideloader/scraper can be expanded to a ten foot wide loader/scraper and aneight foot wide loader/scraper can be expanded to a fourteen foot wideloader/scraper.

When the implement attachment is in its expanded position, means areprovided for allowing the center bucket and the expandable side bucketsto pivot relative to one another to ensure that the leading edge of thecenter bucket and the side buckets are at the same level so that bothcan engage the ground when the frame assembly is tipped forwardly.

Accordingly, it is an object of the present invention to provide animplement attachment which is selectively expandable and retractable toaccommodate different load capacities and/or widths.

These and other objects of the present invention will become apparentwith reference to the drawings, the description of the preferredembodiment and the appended claims.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of one embodiment of the implementattachment of the present invention in its fully retracted position asviewed from the right front.

FIG. 2 is an isometric view of the implement attachment embodiment ofFIG. 1 in its fully retracted position as viewed from the right rear.

FIG. 3 is an isometric view of the implement attachment embodiment ofFIG. 1 in its expanded position as viewed from the right front.

FIG. 4 is an isometric view of the implement attachment embodiment ofFIG. 1 in its expanded position as viewed from the right rear.

FIG. 5 is an isometric view of the frame assembly of the implementattachment embodiment of FIG. 1 as viewed from the right rear.

FIG. 6 is a side view of the frame assembly of the implement attachmentembodiment of FIG. 1 as viewed from the right-hand side of FIG. 5.

FIG. 7 is an isometric view of the pair of bucket extensions for theimplement attachment embodiment of FIG. 1 of the present invention asviewed from the right front.

FIG. 8 is an isometric view of the frame assembly and the side bucketextensions of the FIG. 1 embodiment in their expanded position, withoutthe center bucket, as viewed from the right rear.

FIG. 9 is a side view of the frame assembly and the side bucketextensions of the FIG. 1 embodiment.

FIG. 10 is an isometric view of the center bucket for the implementattachment embodiment of FIG. 1 as viewed from the right rear.

FIG. 11 is an elevational side view of the center bucket for theimplement attachment embodiment of FIG. 1, with the center bucket tippedforwardly.

FIG. 12 is an elevational side view of the implement attachmentembodiment of FIG. 1 with bucket tipped forwardly and showing the sidebucket extensions pivoted forwardly relative to the center bucket.

FIG. 13 is an isometric view of a further embodiment of the implementattachment of the present invention in its fully retracted position asviewed from the right front.

FIG. 14 is a view, partially in section, as viewed along the sectionline 14-14 of FIG. 13.

FIG. 15 is an isometric view of the implement attachment embodiment ofFIG. 13 in its expanded position as viewed from the left front.

FIG. 16 is a view, partially in section, as viewed along the sectionline 16-16 of FIG. 15.

FIG. 17 is an isometric view of the implement attachment embodiment ofFIG. 13 in its expanded and forwardly tipped position as viewed from thelower right rear.

FIG. 18 is an isometric view of the left side bucket extension as viewedfrom the right front.

FIG. 19 is an isometric view of the left-hand bucket extension of theFIG. 13 embodiment as viewed from the right rear.

FIG. 20 is a view, partially in section, as viewed along the sectionline 20-20 of FIG. 18.

FIG. 21 is an isometric rear view of the main frame of the FIG. 13embodiment.

FIG. 22 is an isometric front view of the main frame of the FIG. 13embodiment.

FIG. 23 is a view, partially in section, as viewed along the sectionline 23-23 of FIG. 22.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention is directed to a selectively adjustable implementattachment which can be selectively adjusted to alter its load capacityand/or width. Although the implement attachment of the presentattachment can be attached to the front or back of a self-propelled,driven implement or vehicle such as a truck, tractor, skid steer loaderor the like, it has particular applicability as a front end loaderand/or scraper for snow, dirt, or the like. Further, although theconcept of the adjustable implement attachment of the present inventionhas applicability to a variety of implement attachments, it hasparticular applicability as an expandable bucket or an expandablebucket/scraper combination.

Accordingly, the implement attachment of the present invention will bedescribed with respect to a selectively expandable and retractablebucket/scraper which may be selectively attached and detached from animplement via conventional means. Further, the present invention will bedescribed with respect to two embodiments. A first embodiment shown inFIGS. 1-12 (sometimes referred to as the FIG. 1 embodiment) and a secondembodiment shown in FIGS. 13-23 (sometimes referred to as the FIG. 13embodiment).

With reference first to FIGS. 1-4 showing the first embodiment, theimplement attachment 10 of the present invention includes a plurality ofbucket members including a center bucket 11 and a pair of expandableside buckets or side bucket extensions 12 and 14. The bucket members 11,12 and 14 are operatively connected relative to a main frame or frameassembly 15. As shown, the side bucket extensions 12 and 14 areoperatively connected to be selectively movable relative to the frameassembly 15 and relative to the center bucket 11 between a fullyretracted position as shown in FIGS. 1 and 2 and a fully expandedposition as shown in FIGS. 3 and 4. The center bucket 11 is operativelyconnected to be laterally fixed relative to the frame assembly 15.

As shown best in FIGS. 2, 4, 5 and 6, the frame assembly 15 includes apair of vertically spaced, laterally extending upper 16 and lower 18frame members and a pair of laterally spaced, vertically extendingloader or vehicle mounting plates 19 and 20 which are rigidly secured tothe frame members 16 and 18. In the preferred embodiment, the framemembers 16 and 18 are rigid tubular members. The implement mountingplates 19 and 20 are conventional “Quik-Tach” means which are connectedwith the rearward side of the frame members 16 and 18 by welding or thelike. The plates 19 and 20 function to connect the implement attachmentto a driven vehicle in a conventional manner.

A double acting cylinder means comprised of the interconnected pair ofhydraulic cylinders 22 and 23 are connected to the back surface of afiller plate 38 respectively by welding or brackets, or the like. Withthis mounting, the cylinders 22 and 23 extend laterally outwardly fromopposite sides of the mounting plates 19,20. The laterally extendingcylinders are located approximately midway between the frame members 16and 18. The cylinders 22 and 23 include extendable cylinder rods 24 and25 which are selectively extendable and retractable in oppositedirections from the ends of the cylinders 22 and 23. The cylinders 22and 23 are driven by a hydraulic power source from the implement (notshown) via the hydraulic hoses 26.

The lower frame member 18 includes means in the form of three pairs ofhinge mount brackets 28 for pivotally connecting the center bucket 11 tothe frame assembly 15 as will be described in detail below. In thepreferred embodiment, the hinge mount brackets 28 are rigidly connectedto the rearward face of the lower frame member 18 by welding and eachincludes an opening 29 to receive a pivot pin.

As shown best in FIGS. 5 and 6, a slide track bracket 30 is rigidlyconnected to the upper surface of the upper frame member 16 by weldingor the like. The bracket 30 includes a downwardly extending portion 31which is spaced from the forward surface of the frame member 16 todefine an upper bucket extension slide track 32.

A similar slide track bracket 34 is rigidly secured by welding or thelike to the lower surface of the lower frame member 18. This bracket 34has an upwardly extending portion 35 which is spaced from the frontsurface of the lower frame member 18 to define a lower bucket extensionslide track 36. Both of the slide track brackets 30 and 34 extend forthe entire length of their respective upper and lower frame members 16and 18.

A pair of return spring attachment plates 27 are connected by welding orthe like to the rear surface of the frame member 16. These plates 27include an opening to receive one end of a return spring 33 (FIGS. 2, 4,6 and 12) to limit forward pivotal movement of the frame assembly 15 andthe bucket extensions 12 and 14 relative to the center bucket 11 as willbe described below.

As shown best in FIGS. 5 and 6, a main frame filler plate 38 isconnected between the frame members 16 and 18 by welding or the like.The filler plate 38 is constructed of metal with a sufficient thicknessto assist in providing rigidity to the frame assembly 15 and tosufficiently resist loading and/or scraping forces. The plate 38 isprovided with a forwardly curved portion 39 to accommodate and protectthe cylinder members 22 and 23. The plate 38 and the curved portion 39extend laterally for a substantial portion of the length of the framemembers 16 and 18. In the preferred embodiment, the filler plate 38extends slightly beyond the inner edges of the bucket extensions 12 and14 when in their expanded positions.

With reference to FIGS. 1, 2, 3, 4, 7 and 8, the side bucket extensions12 and 14 are designed for selective lateral movement relative to theframe assembly 15 and the center bucket 11 between a fully retractedposition as shown in FIGS. 1 and 2 and a fully expanded position asshown in FIGS. 2, 4 and 8. Each of the bucket extensions 12 and 14includes top and bottom bucket extension slide guide edges 48 and 49, abucket extension outer side wall 41, a bucket extension inner side wallor reinforcing rib 47 and a bucket extension rear or back wall or plate42. The bottom wall 40 includes an inner side edge 43 and a forward orleading edge 44 which is designed to engage the ground during a loadingor scraping function. A rearward portion of the bottom 40 is rigidlyconnected to the back wall 42 by welding or the like. Preferably, therearward portion of the bottom wall 40 curves upwardly near its rearwardedge as shown by reference character 45 in FIGS. 7 and 9. The back wallor plate 42 includes a lateral cylinder protecting channel 46 and thetop and bottom slide guide edges 48 and 49. As best shown in FIGS. 8 and9, the top slide guide edge 48 is designed to slide laterally within theupper slide track 32, while the bottom slide guide edge 49 is designedto slide laterally within the lower slide track 36.

As shown best in FIG. 7, the back wall 42 is wider in the lateraldirection than the bottom wall 40 between the side wall 41 and the inneredge 43. This additional width (within the slide tracks 32 and 36)functions to support the bucket extensions 12 and 14 in their expandedposition and to resist loading and scraping forces. Preferably, the backwall 42 is at least about 20% wider, more preferably at least about 30%wider and most preferably about 33% wider than its corresponding bottomall 40.

The bucket extension inner side wall which functions as a reinforcingrib 47 is welded to a portion of the back wall 42 and to a top surfaceportion of the bottom wall 40 near the inner edge 43. The rib 47functions to reinforce and provide rigidity to the bucket extensions 12and 14.

Each of the side walls 41 is rigidly connected to the outer edge of theback wall 42 and to the outer edge of the bottom wall 40 by welding orthe like. Preferably, the outer peripheral edges of the side walls 41extend a limited distance beyond the bottom surface of the bottom wall40 and the rearward surface of the back wall 42 as shown. This enablesthe inner peripheral surface of the walls 41 to engage the outer surfaceof one of the side wall portions 55 and 56 of the center bucket 11 asdescribed below. Each of the side walls 41 includes an opening near itsrearward edge to receive a respective one of the outer ends of thecylinder rods 24 and 25 (FIG. 8). Specifically, in the preferredembodiment, an outer threaded end of each of the cylinder rods 24 and 25extends through a corresponding opening in one of the side walls 41 andis connected thereto by a threaded nut 50.

With this structure, selected extension and retraction of the cylinders22 and 23 and their respective cylinder rods 24 and 25 will cause thebucket extensions 12 and 14 to slide outwardly and inwardly relative tothe frame assembly 15. This sliding movement is guided by the upper andlower slide guide edges 48 and 49 of the back walls 42 within the slidetracks 32 and 36.

The center bucket 11 is shown best in FIGS. 10 and 11, with referencealso being made to FIGS. 1-4 showing relationship of the center bucketmember 11 to the frame assembly 15 and the expandable side bucketmembers 12 and 14. The center bucket 11 includes a bottom wall 51, upper52 and lower 54 rear wall frame members and a pair of side wall portions55 and 56. The bottom wall 51 includes a front or leading edge 58, apair of side edges and a rearward portion 59. The side edges comprise amain side edge portion 62 and a forward side edge portion 53. Therearward portion 59 extends upwardly and rearwardly from the mainportion of the bottom wall 51. Each of the side wall portions 55 and 56includes a rearward leg or portion 60, a bottom wall portion which isconnected with and defines the bottom wall side edges 62 and a forwardlyextending portion 61. Preferably the side wall portions 55 and 56 areintegrally formed from a metal material having sufficient thickness toresist the various forces exerted on the center bucket during use. Asshown in FIG. 11, the rearward portion 60 is rigidly connected betweenthe lower frame member 54 and the upper frame member 52 by welding,while the bottom wall portion is connected with and define the sideedges 62 of the bottom wall 51 by welding. The forwardly extendingportion 61 extends from the upper end of the portion 60 to the forwardend of the portion 62. In FIG. 10, the side wall portions 60, 61 and 62define an opening 64 in each of the side wall portions 55 and 56 toaccommodate lateral movement of the side buckets 12 and 14 as will bedescribed in greater detail below. Preferably, the openings 64 aresufficiently large to permit passage of walls 40 and 42 of the bucketextensions 12 and 14 during expansion and retraction movement, butslightly smaller than the side walls 41.

As shown in FIGS. 1, 3 and 10, the forward side edge portions 53 are atboth ends of the forward edge 58 of the bottom wall 51. These edgeportions 53 extend laterally outwardly from the side edge portion 62.This lateral extension of the edge portions 53 insures that when thebucket extensions 12 and 14 are in their fully extended positions, therewill be a complete clean sweep across the entire width of the expandedbucket.

With continuing reference to FIGS. 10 and 11, a plurality of pin hingemembers 65 are rigidly connected to the bottom frame member 54 bywelding or the like and are laterally spaced so that they mate with thethree pairs of hinge mount brackets 28 of the frame assembly 15. Thus,when assembled, the center bucket 11 is connected with the frameassembly 15 for limited pivotal movement. Such pivotal movement ispermitted by positioning the pin hinge members 65 between respectivepairs of hinge mount brackets 28 and inserting a pivot pin through therespective openings in the pin hinges 65 and the brackets 28.

A pair of vertically extending frame members 66 are rigidly connected tothe outer edge of the side wall portion 60 and between the upper andlower frame members 52 and 54. These members 66 function to reinforceand provide rigidity to the rearward frame portion of the center bucket11. As described in greater detail below, these members 66 also functionto limit the rearward pivotal movement of the frame 15 and bucketextensions 12 and 14 relative to the center bucket 11.

A pair of return spring attachment pins 37 are connected with a rearface of the frame members 66 by welding or the like. These pins 37 havea portion extending inwardly from the frame members 66 for connection toan end of the return springs 33 (FIGS. 2, 4, 6 and 12). The pins 37 mayinclude a spring retaining groove or opening if desired.

When the above-described structure is fully assembled, the frameassembly 15 and each of the bucket extensions 12 and 14 are operativelyconnected with the implement via the mounting plates 19 and 20 andconventional attachment means. Thus, the frame assembly 15 and thebucket extensions 12 and 14 raise, lower and tilt in response tocorresponding movement of the implement attachment means. The bucketextensions 12 and 14 are also movable laterally relative to the frameassembly 15 between a fully retracted and a fully expanded position.When fully assembled, the center bucket 11 is connected with the mainframe assembly 15 via the hinges 65 and the hinge mount brackets 28.

When the bucket extensions 12 and 14 are in their fully or partiallyretracted positions, the bottom surfaces of the side bucket bottom walls40 are in substantial engagement with the top surface of the centerbucket bottom wall 51. When the side bucket extensions 12 and 14 are intheir fully retracted positions, the inner peripheral surfaces of theside walls 41 are also in substantial engagement with the outer surfacesof the center bucket side wall portions 55 and 56. Because the sidewalls 41 are slightly larger than the openings 64 in the side walls 55and 56, the openings 64 will be fully covered by the side walls 41 whenthe bucket extensions 12 and 14 are in their fully retracted position.When the implement attachment is in its fully or partially retractedposition, pivotal movement of the center bucket 11 relative to the frameassembly 15 and the bucket extensions 12 and 14 is prevented.Specifically, in this position, rearward pivotal movement of the centerbucket 11 is prevented because of the substantial engagement between therespective bucket bottom walls 40 and 51, while forward pivotal movementof the center bucket 11 is prevented because of substantial engagementbetween the forward surface of the frame members 66 and the rearwardsurface of the upper frame member 16.

When the bucket extensions 12 and 14 are in their fully expandedposition, the inner edges 43 of the side bucket bottom walls 40 areoutside the corresponding center bucket side edge portions 62. In thisposition, the center bucket bottom walls 40 are no longer in substantialengagement with the center bucket bottom wall 51. Thus, limited rearwardpivotal movement of the center bucket 11 relative to the main frame 15and the bucket extensions 12 and 14 (or forward pivotal movement of theframe assembly 15 and bucket extensions 12 and 14 relative to the centerbucket 11) is permitted. This limited rearward pivotal movement of thecenter bucket 11 permits the leading edges 44 of the side buckets 12 and14 to engage the ground or other supporting surface 70 when theimplement attachment 10 is tipped forwardly as shown in FIG. 12, despitethe fact that the edges 44 are positioned rearwardly of the edge 58. Inthis position, even if the edges 43 are a limited distance outside theside edge portions 62, the outwardly extending side edge portions 53will insure a complete clean sweep across the entire width of theexpanded bucket. This pivotal movement is limited by the return springassembly comprised of the return springs 33, the attachment plates 27and the pins 37. Each of the springs 33 is a tension spring with one endconnected with a respective plate 27 on the frame member 16 and anopposite end connected with a respective pin 37 on the frame member 66.Then as the side bucket extensions 12 and 14 pivot forwardly relative tothe center bucket 11, the springs 33 are tensioned to limit such pivotalmovement.

Having described the structure of the implement attachment of thepresent invention, its operation can be understood as follows. First, ifthe implement attachment is not connected with the driving vehicle orimplement, the attachment is connected with the implement in aconventional manner via a conventional connection between the drivenimplement and the mounting plates 19 and 20 (FIGS. 2, 4, 5 and 6). Thehydraulic hoses 26 for the cylinders 22 and 23 are also connected to ahydraulic power source on the driven implement.

When attached to the driven implement, the implement attachment 10 ofthe present invention is ready for use. In its fully retracted positionas shown in FIGS. 1 and 2, the bucket extensions 12 and 14 are fullyretracted via the cylinders 22 and 23 so that the inner surfaces of thebucket extension side walls 41 engage the outer surfaces of the sidewall portions 55 and 56. In this position, as shown in FIG. 1, thebottom walls 40 of the bucket extensions 12 and 14 are supported on theupper surface of the center bucket bottom wall 51 and the center bucket11 is movable in unison with the frame assembly 15 and the bucketextensions 12 and 14. In this position, the implement attachment 10 canbe used as a conventional bucket loader to lift, carry and dump snow,dirt or other materials or can be used as a scraper with a width equalto the width of the center bucket member 11. In this retractedconfiguration, the center bucket leading edge 58 functions as the solescraping or cutting edge.

To convert the implement attachment 10 to its fully expanded position,the hydraulic cylinders 22 and 23 are actuated by the operator on thedriven implement. This causes the bucket extensions 12 and 14 to movelaterally outwardly relative to the frame assembly 15 and the centerbucket 11. When the side buckets 12 and 14 are in their fully expandedor extended positions as shown in FIGS. 3 and 4, the inner edges 43 ofthe side bucket bottom walls 40 are positioned outside the outer sideedge portions 62 of the center bucket bottom wall 51. This relativeposition of the side edges 43 and the side edge portions 62, togetherwith the pivotal connection between the center bucket 11 and the frameassembly 15 enables the side buckets 12 and 14 (and the frame assembly15) to pivot forwardly a limited distance relative to the center bucket11 when the attachment is tipped. The amount of this limited forwardmovement is constrained by the return spring assembly comprised of thereturn springs 33, the attachment plates 27 and the pins 37 and by theangle at which the attachment is tipped. In contrast, rearward pivotalmovement of the frame assembly 15 and the side extension buckets 12 and14 relative to the bucket 11 beyond the positions shown in FIGS. 1 and 2is still prevented as a result of the engagement and interferencebetween the reinforcing frame members 66 and the top frame member 16.

This limited forward pivotal movement of the bucket extensions 12 and 14relative to the center bucket 11 is desirable, particularly when theattachment is used in a scraping function and the attachment is tippedor tilted forwardly. When the expanded bucket is tilted forwardly, withthe leading edge 58 in contact with the ground, such pivotal movementallows the leading edges 44 of the side bucket extensions 12 and 14 tobe at the same level relative to the ground or supporting surface 70(FIG. 12) as the leading edge 58 of the center bucket 11. This relativepivotal movement is automatic and results from engagement of the leadingedge 58 of the center bucket 11 with the ground 70 when the expandedbucket is tipped forwardly. Thus, regardless of the relative pivotalposition of the bottom walls 40 and 51 relative to the ground (except asconstrained by the return spring assembly), the leading edges 44 and 58of the bottom walls 40 and 51, respectively, will automatically adjustto ground level. When in its fully expanded position, the implementattachment functions as a loader or scraper with an expanded loadcapacity and width.

To return the implement attachment to its retracted position, theattachment is tilted back or raised so that the frame members 66 of thebucket 11 and the upper frame member 16 are in substantial engagement.In this position, the bottom walls 40 and 51 are substantially parallelto one another, with the bottom surface of the bottom wall 40 even withor slightly above the top surface of the bottom wall 51. The cylinders22 and 23 are then actuated to retract the extensions 12 and 14 untilthey reach their fully retracted positions.

A further embodiment of the implement attachment of the presentinvention is shown in FIGS. 13-23. Similar to the embodiment of FIGS.1-12, the embodiment of FIGS. 13-23 is an adjustable implementattachment which can be selectively adjusted to alter its load capacityand/or width. It includes a center bucket member 75, a pair of sidebucket members or bucket extensions 76 and 78 and a main frame or frameassembly 79. The bucket extensions 76 and 78 are moveable outwardly andinwardly between a fully retracted position as shown in FIG. 13 and afully expanded position as shown in FIGS. 15 and 17. The movement of thebucket extensions 76 and 78 between its retracted and expanded positionsis accomplished by a pair of hydraulic cylinders (not shown in FIGS.13-22) similar to the cylinders 22 and 23 of the FIG. 1 embodiment.These cylinders would be connected between the main frame 79 and thebucket extensions 76 and 78.

Many of the structural features of the FIG. 13 embodiment are the sameas or similar to the FIG. 1 embodiment. For example, the center bucket75 of the FIG. 13 embodiment is substantially the same as the centerbucket 11 of the FIG. 1 embodiment. Accordingly, the detaileddescription of the FIG. 1 embodiment is incorporated into the disclosureof the FIG. 13 embodiment. The main difference between the twoembodiments relates to the means for guiding the lateral movement of thebucket extensions 76 and 78 relative to the center bucket 75 and themain frame 79 between their retracted and expanded positions.Accordingly, the main structural differences between the two embodimentsinvolve the slide or guide rails 81 and 82 of the main frame 79 and thecorresponding slide or guide rails 100, 101 and 102 of the bucketextensions 76 and 78.

With general reference to FIGS. 13-22 and specific reference to FIGS.21, 22 and 23, the main frame 79 includes a plurality of laterallyextending slide or guide rails comprising a pair of outer slide rails 81and a pair of inner slide rails 82. As shown, the inner slide rails 82are tubular in construction with a generally trapezoid cross-sectionalconfiguration. Thus, each of the inner slide rails 82 includes a pair ofbeveled exterior slide or guide surfaces 84. The pair of outer sliderails 81 are also tubular in construction and each includes an innerfacing beveled exterior slide or guide surface 85 adjacent to one of theinner slide rails 82. The slide rails 81 and 82 are rigidly connectedvia welding or the like to a conventional implement attachment meanssuch as the pair of “Quik-Tach” plates 86. Such Quik-Tach plates 86provides a mounting arrangement for a skid steel vehicle. The sliderails 81 and 82 are further rigidly interconnected via welding neartheir ends via the pair of retainer tubes or frame members 88. Aplurality of filler plates 83 are provided between adjacent rails 81,82and between the plates 86 to provide a bucket back between the bucketextensions 76 and 78. These filler plates 83 are welded to the rearsurface of the slide rails 81 and 82.

As shown best in FIG. 23, the rails 81 and 82 are vertically spaced fromone another to provide a sliding recess or gap 87 between adjacent rails81, 82. These gaps 87, defined by the surfaces 84 and 85 and the forwardsurfaces of the plates 86 and 83, provide sliding recesses for thebucket extensions 76 and 78. A plurality of hinge members 89 and pivotpins 90 are rigidly secured to the bottom slide rail 81 for pivotalconnection to the center bucket 75 as shown and described with respectto the FIG. 1 embodiment.

With continuing general reference to FIGS. 13-23 and more specificreference to FIGS. 18-20, each of the bucket extensions includes abottom wall 91, a rear wall 92, an outer side wall 94, an inner sidewall 95 and a front edge 96. These elements are substantially the sameas corresponding elements of the FIG. 1 embodiment. The back wall 92 andthe bottom wall 91 are rigidly secured such as by welding or the like toa pair of skid bars 98. A tubular member 99 is formed from the top endof the rear wall 92 to provide stability and reinforcement to the bucketextensions 76 and 78. An end cap may be welded to the open inner end ofthe member 99.

A plurality of slide or guide rails 100, 101 and 102 are rigidly securedto the rearward side of the skid bars 98 by welding or the like. Asshown, these slide rails 100-102 extend from the outer side wall 94,along the rear wall 92 and for a limited distance past the inner sidewall 95. The slide rails 100-102 extend laterally and are verticallyspaced from one another to provide a sliding recess or gap 103 (FIG. 20)between adjacent rails 100-102. Each of the slide rails 100-102 istubular in construction and has a generally trapezoid cross section witha pair of beveled surfaces 104 extending outwardly from the skid bars 98as shown best in FIG. 20. The inner ends of the slide rails 100-102 areprovided with a beveled end 105.

With the above-described structure, the slide rails 100-102 of each ofthe side buckets 76 and 78 are designed to slide laterally within theslide recesses 87 (FIG. 23) of the main frame 79. During this slidingrelationship, the beveled surfaces 104 of the slide rails 100-102 engagethe beveled surfaces 84 and 85 of the slide rails 82 and 83,respectively.

Having described the structural features of the FIG. 13-23 embodiment,its operation can be understood as follows. When the implementattachment is in its fully retracted position as shown in FIG. 13, itcan be used as a conventional loader and/or scraper with a width asshown. When it is desired for the width of the attachment to beincreased, the actuating cylinders 22 and 23 (shown in FIG. 8 of theFIG. 1 embodiment) are actuated. This causes the bucket extensions 76and 78 to move outwardly to their expanded position as shown in FIG. 17.When in this expanded position, the bucket extensions 76 and 78 moveoutwardly past the outer edges of the center bucket 75. With thismovement, the bottom wall 91 and front edge 96 of the bucket extensions76 and 78 clear the center bucket 75. This permits limited pivotalmovement between the center bucket 75 on the one hand and the bucketextensions 76 and 78 and the main frame 79 on the other. As describedabove with respect to FIGS. 1-12 and as shown in FIGS. 15, 16 and 17,this enables the front edge 58 of the center bucket 75 as well as thefront edges 96 of the bucket extensions to contact the ground for ascraping function regardless of the angle which the implement attachmentforms with the supporting surface. This is accomplished in the samemanner as in the FIG. 1 embodiment. Thus, if and when the attachment istilted forwardly as shown in FIGS. 15, 16 and 17, the leading edge 58 ofthe center bucket 75 and the leading edge 96 of the bucket extensionsremain in contact with the ground. To accommodate this, the main frame79 and the bucket extensions are allowed to pivot forwardly relative tothe center bucket 75. The difference between the angle which the centerbucket 75 makes with the ground and the angle which the extensions 76and 78 make with the ground, when the attachment is tilted forwardly, isreferred to as the float angle. If desired, a spring such as the spring33 of the FIG. 1 embodiment or other means can be provided between theframe 79 and a portion of the center bucket 75 to limit the permittedpivotal movement between the frame 79 and bucket 75.

If desired, a retaining bar 108 (FIG. 15) can be welded to the frontedges of the slide rails 100-102 to provide stability and reinforcementand to prevent the slide rails 100-102 and thus the bucket extensions 76and 78 from pivotable movement relative to the retainer tubes 88 whenthe bucket extensions are in their expanded positions.

Although the description of the preferred embodiments has been quitespecific, it is contemplated that various modifications could be madewithout deviating from the spirit of the present invention. For example,without limitation, although the embodiment of FIGS. 13-23 show thevarious slide rails with a trapezoidal cross-section, a variety of othercross-sectional configurations and other mechanisms could be utilized tofacilitate lateral movement between the main frame and the side bucketextensions. Further, the slide rails could be solid as opposed totubular. Accordingly, it is intended that the scope of the presentinvention be dictated by the appended claims, rather than by thedescription of the preferred embodiment.

1. An expandable implement attachment comprising: a frame assemblyselectively connectable to a driven vehicle; a center member hingedlyconnectable to said frame assembly, said center member comprising aframe, a bottom wall, a leading edge, end plates and an open rearportion; a first bucket member operatively connected to said frameassembly and comprising a leading edge; a second bucket memberoperatively connected to said frame assembly and comprising a leadingedge; and said first and second bucket members being laterally moveablebetween a retracted position and an expanded position relative to thecenter member, said center member connectable to said frame assemblyindependently of the first and second bucket members, whereby the threeleading edges lie on a single plane independent of an angle of tilt ofsaid first, second and center members when said members are in anoperating position.
 2. The implement attachment of claim 1 wherein thefirst and second bucket members are laterally moveable relative to saidframe assembly.
 3. The implement attachment of claim 2 wherein saidfirst and second bucket members are laterally moveable relative to saidframe assembly and said center member between a fully retracted positionin which a substantial portion of each of said first and second bucketextensions is positioned between said end plates and a fully expandedposition in which a substantial portion of each of said first and secondbucket members is positioned laterally outside of said end plates. 4.The implement attachment of claim 3 wherein each of said end platesincludes an opening to accommodate lateral movement of said first andsecond bucket members.
 5. The implement attachment of claim 1 whereinsaid center member is operatively connected to said frame assembly topermit limited pivotal movement between said center member and saidframe assembly.
 6. The implement attachment of claim 1 including a powercylinder positioned between said frame assembly and said first andsecond bucket members.
 7. The implement attachment of claim 1 whereinsaid frame assembly includes a plurality of laterally extending framemembers.
 8. The implement attachment of claim 7 wherein said framemembers include upper and lower frame members, each having a slidetrack.
 9. The implement assembly of claim 8 wherein said first andsecond bucket members includes a slide plate for sliding movement withinsaid slide tracks.
 10. The implement assembly of claim 7 wherein saidframe members comprise a plurality of first slide rails and at least oneof said first and second bucket members having a plurality of laterallyextending second slide rails, said first and second slide rails matingwith one another to permit relative lateral sliding movement betweensaid first and second slide rails.
 11. An expandable implementattachment comprising: a frame assembly selectively connectable to adriven vehicle, said frame assembly including a plurality of laterallyextending frame members; a first bucket member operatively connected tosaid frame assembly; a second bucket member operatively connected tosaid frame assembly; and at least one of said first and second bucketmembers being laterally moveable relative to the other of said first andsecond bucket members between a retracted position and an expandedposition, said frame members comprising a plurality of first slide railsand at least one of said first and second bucket members having aplurality of laterally extending second slide rails, said first andsecond slide rails mating with one another to permit relative lateralsliding movement between said first and second slide rails, wherein saidfirst and second slide rails have generally trapezoidal cross-sections.12. The implement assembly of claim 10 wherein said frame assemblyincludes a plurality of filler plates between said first slide rails.13. The implement assembly of claim 2 wherein each of said first andsecond bucket members includes a side wall and a bottom wall, saidbottom wall carrying the leading edge.
 14. An implement attachmentcomprising: a frame selectively connectable to a vehicle; a centermember hingedly connectable to said frame, said center member comprisinga leading edge and defining an open rear portion; a first bucket memberlaterally moveable relative to said frame, laterally and pivotallymoveable relative to said center member and comprising a leading edge;and a second bucket member laterally moveable relative to said frame,laterally and pivotally moveable relative to said center member andcomprising a leading edge.
 15. The implement attachment of claim 14,wherein said first and second bucket members move laterally to theextent that said first and second bucket members do not substantiallyoverlie said center member.
 16. The implement attachment of claim 14,wherein the leading edges of the center member and the first and secondbucket members overlap.
 17. The implement attachment of claim 14,wherein the leading edges of the center member and the first and secondbucket members lie on a single plane when said members are in anoperating position.
 18. The implement attachment of claim 14, wherein,when in an operating position, the center member is at angle of tiltrelative to a surface on which the attachment is being used and thefirst and second bucket members are at another angle of tilt relative tothe surface.
 19. The implement attachment of claim 18, wherein the threeleading edges lie on a single plane independent of the angle of tilt ofsaid first, second and center members when said members are in anoperating position.